A few hints for new players

[Ranakastrasz]

Yep, they stack.  This won't make them push Creeper 'faster', but they will be able to hold back a greater density of Creeper.

Im not quite sure if it is true that they will not push creeper 'faster' If they stack, and the 'spread bias' is focused in that direction, with twice the force of one, then you can move twice as much creeper in that time. Also, considering the evaporation of creeper, I think that it does move it faster.

However, Since I did not code the system, I am just guessing.

[Kithros]

Essentially creeper moves every 2 frames from what I understand (half of the map each frame) - and creeper can only move 1 subcell each time it moves, so no matter how strong the fields etc. are the creeper will never move faster than that - the strength of the fields only efects how much of the creeper moves each time. Because of some interactions with evaporation of creeper (creeper under 10 density evaporates instantly) this may make creeper appear to move faster/slower, but it's typically just that the creeper is actually disappearing on one end or the other rather than actually moving at a different speed.

[weekendgamer]

I just had to post this here because this hotkey isn't documented and might be forgotten.

Equals sign(=) - show FPS

[mthw2vc]

It is documented and will never be forgotten - by betas. (That hotkey also works in CW1, for reference)

[TrickyDragon]

lol my first time reading this entire post, i never knew about the (=) lol  i gotta try that now xD

[Men Dude]

When you pause the game, you can press 'N' to play 1 frame of the game. Hold it and it will look like the game is not paused. :)

[Keybounce]

How do you rotate reactors like that? I can only get them vertical, so I'm digging every other row of dirt for space.

[Karsten75]

How do you rotate reactors like that? I can only get them vertical, so I'm digging every other row of dirt for space.

It would have been far better to create your own post rather than resurrect an 11 year-old post (but kudos for searching). 
Build direction is map-specific. In, for instance, code missions, the build direction is specified: 
 
In a specific map, the build direction is indicated in the bottom control bar: 
 

[Keybounce]

Thank you.